There has been available a conventional pulser for a medical ultrasound system having a drive circuit for converting a predetermined input pulse into a high-voltage pulse to be thereby sent out, and an output transistor to be driven for switching by the high-voltage pulse, for sending out an output pulse for oscillation to an ultrasonic transducer (refer to, for example, JP-B No. 06 (1994)-53113). Besides, there has been available a driver (refer to, for example, JP-A No. 2005-340624 and JP-A No. 2000-156495) for driving a plasma display panel, or a pulser similarly having a driver circuit disposed in a front stage, and an output transistor connected to a succeeding stage thereof, in a driver (refer to, for example, JP-A No. 11 (1999)-205112) for driving a high-voltage resistant power integrated circuit for household appliance use, automobiles use, industrial use, and so forth.
Further, there has been available a conventional pulser for a medical ultrasound system (refer to, for example, Supertex Inc., HV732 data sheet) comprising a gate drive circuit made up of voltage level translators, and voltage buffers, for receiving logical pulses to thereby drive a gate unit in a succeeding stage, and a transducer drive circuit made up of an output transistor and the gate unit including a clamping circuit, for driving an ultrasonic transducer in a succeeding stage, wherein the gate drive circuit is coupled to the transducer drive circuit via capacitors.